Making Maths: String and Circles

Age 7 to 14
Challenge Level

This can be done well on paper with a ruler and coloured pens, but it's a lot of fun to get busy with a hammer, nails and string if you can.

You will need:

  • A large sheet of paper
  • Scissors
  • Pencil
  • A piece of wood
  • 16 nails
  • String or wool

What to do:

  1. Cut out a large circle of paper - tracing around a small plate is easy.
  2. Mark off 16 equally spaced points around the circle by folding it half, half again, half again, and half again. Open it up then mark the places clearly with a pen.
  3. Smooth out the paper and tape it to a piece of wood.
  4. Carefully hammer in 16 nails, one on each point around the circle (Watch your fingers!)
  5. Tie some string or wool to one of the nails. Choose the space you are going to leave between looping the string around a nail. Continue around until you return to the start.

    For example, the pattern below was made by linking every third nail.
    Pattern with string on nails
  6. Try out different designs. If you find one you really like; you could paint the wood and use coloured string to make a wall plaque.
You might like to try the problem Stars too.